Texas scientists have used embryonic stem cells to heal a severely damaged artery in a baboon.

A team from the Texas Biomedical Research Institute in San Antonio, led by John L. VandeBerg, Ph.D., took embryonic stem cells from baboons to produce a fully functional artery.

To do this, the team extracted cells that line the surface of a part of an artery and replaced them with cells that were derived from embryonic stem cells. Both ends of the arterial segment were then connected to plastic tubing inside a bioreactor, which encourages cells to grow.

Fluid was then pumped through the artery under pressure to mimic blood, and a different fluid was then used to soak the outside of the artery. Only three days later, the inner surface began to regenerate, and after two weeks, the inside of the artery was completely restored to a functional state.

The team even stripped another artery without placing the stem cells inside to see if it was the stem cells that did the rejuvenating. The artery without the stem cells didn't heal and never became functional.

"We first cultured the stem cells in petri dishes under special conditions to make them differentiate into cells that are the precursors of blood vessels, and we saw that we could get them to form tubular and branching structures, similar to blood vessels," said VandeBerg. "Just think of what this kind of treatment would mean to a patient who had just suffered a heart attack as a consequence of a damaged coronary artery. And this is the real potential of stem cell regenerative medicine -- that is, a treatment with stem cells that regenerates a damaged or destroyed tissue or organ."